Debt Instrument, Increase In Principal Amount As A Percent Of Treasury Disbursements

No definition available.

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- Definition

Debt Instrument, Variable Rate Floor

+ References

No definition available.

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- Definition

Payroll Support Program, Total Funding Provided

+ References

No definition available.

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- Definition

Payroll Support Program, Funding Provided, Amounts Received Through Loans

+ References

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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- Definition

The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

+ References

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- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

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Debt - Narrative (Details) - USD ($)				2 Months Ended	3 Months Ended	12 Months Ended
Debt - Narrative (Details) - USD ($)	Sep. 28, 2020	Jul. 02, 2020	Apr. 20, 2020	Feb. 25, 2021	Dec. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Feb. 15, 2021	Jan. 15, 2021	Jun. 30, 2020	Apr. 07, 2020	Mar. 20, 2020	Mar. 09, 2020
Debt Instrument [Line Items]
Total funding provided under the Payroll Support Program			$ 5,100,000,000
Funding provided through loans under the Payroll Support Program			$ 1,500,000,000
Proceeds from issuance of debt						$ 16,044,000,000	$ 1,847,000,000	$ 1,594,000,000
Long term debt					$ 27,301,000,000	27,301,000,000	14,733,000,000
Subsequent Event
Debt Instrument [Line Items]
Total funding provided under the Payroll Support Program										$ 2,600,000,000
United Airlines, Inc.
Debt Instrument [Line Items]
Proceeds from issuance of debt						$ 16,044,000,000	1,847,000,000	$ 1,594,000,000
Secured Debt \| Revolving Credit Facility
Debt Instrument [Line Items]
Fixed interest rate					1.49%	1.49%
Long term debt					$ 1,000,000,000	$ 1,000,000,000	0
Secured Debt \| Revolving Credit Facility \| United Airlines, Inc.
Debt Instrument [Line Items]
Credit agreement					2,000,000,000.0	2,000,000,000.0
Available under revolving credit facility					$ 1,000,000,000.0	1,000,000,000.0
Proceeds from lines of credit		$ 1,000,000,000.0				$ 1,000,000,000.0
Secured Debt \| LIBOR \| Revolving Credit Facility \| United Airlines, Inc.
Debt Instrument [Line Items]
Basis spread on variable rate		2.25%
Variable rate floor		0.00%
Secured Debt \| Alternative Rate Based on Certain Market Interest Rates \| Revolving Credit Facility \| United Airlines, Inc.
Debt Instrument [Line Items]
Basis spread on variable rate		1.25%
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Commitment fee percentage		0.75%
Line of Credit \| Revolving Credit Facility \| United Airlines, Inc.
Debt Instrument [Line Items]
Available under revolving credit facility		$ 1,000,000,000.0
PSP Note \| Unsecured Debt
Debt Instrument [Line Items]
Term of debt			10 years
Fixed interest rate					1.00%	1.00%
Long term debt					$ 1,501,000,000	$ 1,501,000,000	0
PSP Note \| Unsecured Debt \| Years One through Five
Debt Instrument [Line Items]
Fixed interest rate					1.00%	1.00%
PSP Note \| Unsecured Debt \| Years Six through Ten \| SOFR
Debt Instrument [Line Items]
Basis spread on variable rate					2.00%
Mileage Plus Senior Secured Notes \| Secured Debt
Debt Instrument [Line Items]
Aggregate principal amount		$ 3,800,000,000
Fixed interest rate		6.50%			6.50%	6.50%
Long term debt					$ 3,800,000,000	$ 3,800,000,000	0
MileagePlus Term Loan Facility \| Secured Debt
Debt Instrument [Line Items]
Fixed interest rate					5.49%	5.49%
Long term debt					$ 3,000,000,000	$ 3,000,000,000	0
MileagePlus Term Loan Facility \| Line of Credit
Debt Instrument [Line Items]
Aggregate principal amount		$ 3,000,000,000.0
Proceeds from issuance of debt		$ 3,000,000,000.0
MileagePlus Term Loan Facility \| Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		5.25%
Variable rate floor		1.00%
CARES Act Credit Agreement \| Line of Credit
Debt Instrument [Line Items]
Aggregate principal amount	$ 520,000,000
Proceeds from issuance of debt	520,000,000
Credit agreement	$ 7,500,000,000
CARES Act Credit Agreement \| Line of Credit \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Variable rate floor	0.00%
Used Aircraft Facility \| Secured Debt
Debt Instrument [Line Items]
Aggregate principal amount														$ 2,000,000,000
Long term debt					14,538,000,000	14,538,000,000	$ 11,585,000,000
Spare Parts Facility \| Secured Debt
Debt Instrument [Line Items]
Aggregate principal amount													$ 500,000,000
Spare Engines Facility \| Secured Debt
Debt Instrument [Line Items]
Aggregate principal amount												$ 250,000,000
Term Loan Credit and Guaranty Agreement \| Bridge Loan
Debt Instrument [Line Items]
Aggregate principal amount											$ 200,000,000
Pass-Through Certificates
Debt Instrument [Line Items]
Long term debt					12,100,000,000	12,100,000,000
Borrowings Financing Aircraft Purchases \| Secured Debt
Debt Instrument [Line Items]
Aggregate principal amount					691,000,000	691,000,000
Special Facility Revenue Bonds \| Secured Debt
Debt Instrument [Line Items]
Aggregate principal amount					$ 295,000,000	$ 295,000,000
Fixed interest rate					4.00%	4.00%
Special Facility Revenue Bonds \| Mortgage
Debt Instrument [Line Items]
Long term debt					$ 159,000,000	$ 159,000,000
PSP2 Note \| Unsecured Debt \| Subsequent Event
Debt Instrument [Line Items]
Funding provided through loans under the Payroll Support Program									$ 753,000,000
Term of debt				10 years
Increase in principal amount as a percent of treasury disbursements									30.00%
PSP2 Note \| Unsecured Debt \| Years One through Five \| Subsequent Event
Debt Instrument [Line Items]
Fixed interest rate									1.00%
PSP2 Note \| Unsecured Debt \| Years Six through Ten \| SOFR \| Subsequent Event
Debt Instrument [Line Items]
Basis spread on variable rate				2.00%